Mercedes-Benz Q&A

1994 Mercedes-Benz S500 Question: door vaccume and air conditioner

I have a Mercedes S500...I lost the vaccume to the drivers side door and it doesnt suck the door closed. When I turn on the air conditioner the heat comes out the drivers side and passenger side vents and also where the brake is ..hot air blows down and it is extremly hot.

The heat from air conditioner problem is caused by a stuck/failing heater servo/heater valve. An expensive part. Try to buy it used. Contact Sun Valley Mercedes Dismantlers and ask for Marc. He is very knowledgable and may have a valve that fits your car with less age or mileage than yours. Labor to put it in is nominal and Sun Valley warrantees parts for I think a year.

I have vacuum problem also, but have not been willing to incur the cost to try to fix it.

how do i access to this valve? and just in case any other suggestions? I see there is a panel at the firewall(back of engine under the hood) is this the main air dist box? ok access it seems.thanks for your help,new at mercs. nate b777 tech

your door may also have vacume problems: Most common is the one way ck valve ,but you have to remove the door panel to gain access,if you can blow or suck one way only then valve ok. next follow the vaccume line to the door jamb just below the hinge, it almost always breaks in that vicininity. effect repair accordingly! good luck